 <div class="back-bt"></div>
<section>
	<h2>更换背景</h2>
	<ul class="clearfix" id="bg_images">
		<li data-image="#7495BC"><div class="no-image">无背景</div></li>
		<li data-image="images/app_bg2.jpg"><img src="images/app_bg2_min.jpg" alt="sky" /></li>
		<li data-image="images/app_bg3.jpg"><img src="images/app_bg3_min.jpg" alt="friend" /></li>
		<li data-image="images/app_bg.jpg"><img src="images/app_bg_min.jpg" alt="fly" /></li>
	</ul>
</section>
<div class="bg"></div>